Pump-regulating mechanism.



R. CONRADER. PUMP REGULATING MECHANISM.

APPLICATION FILED APR-9,1913.

Patented Apr. 13,1915.

x W 1 x RUDOLPH CQNJRdDEE-t, Uh ERTE, PENNSYLVANIA.

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Specification oi Letters Patent.

Patented Apr. 113, 119115..

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llt has been common practice heretofore to provide relief devices for pumps. This is a well-known mechanism and its function is to stop or decrease thepumping action of.

the compressor to prevent an accumulation of pressure in the receiver. .There are two general types of these devices, one operat ing on the discharge'of. the pump cylinder either "by the control 'of the discharge valves stopping the pumping action or allowing the pumped fluid to waste and the other operating upon the intake of the receiver and thus controlling the pumping action of the compressor; In connection with these relief devices means'have been provided for controlling the valve of the'pump motor so that when the relief is thrown in and the pump is relieved of its load, the controlling valve of the motor is closed so that the motor will deliver power in proportion to the load.

The object of this invention is to auto matically retard the opening of the motor valve so as to have it conform to the discharge pressure, that is to say, the valve is gradually opened as the discharge pressure rises so that the motor receives power gradually increasing as the load increases. After the discharge pressure reaches the normal pressure, the valveis operatedas heretofore variation.

in; conjunction with and according to the action of the relief device.

In the accompanying drawings l have shown the invention as operating'on an intake pipe of a compressor.

1 marks the compressor cylinder, 2 the steam chest of the motor, 3 the base to which these are connected, a the intake to the compressor and 5 the discharge from the compressor. It will be understood that the dis charge pipe 5 represents the receiver and is subjected to practically receiver pressure.

The motor controlling valve has the body 6 in which is the "double, diaphragm 7. A removable seat 8- is secured in-the double diaphragm 7 and operates in connection with the usual double diaphragm valve 9.

The relief devices comprises the valve .bodyll arrangedon the intake. lit has the diaphragm --12 with the valve passage pro- 'vided with the seat 13. The relief valve 1 operates with relation to the seat 13. It is carried by a stem 15. The stem 15 is secured to a piston 16. The piston 16 is arranged in a cylinder 17. A spring 18 is arranged around the stem 15 between the piston 16 and a spider 18 The spring tends to open the valve 14. The cylinder 17 is connectedby a passage 19 with the valve controlled passage 20. A needle valve 21 operates in the passage 20. The needle valve is carried by a piston 22. The piston 22 operates in a cylinder 23. A. spring 2 1 is arranged in the cylinder against the piston 22 and the spring is adjusted by the screw 25. A pipe 26 connects the receiver, in this case the discharge pipe 5, with the cylinder 23. A minute opening 27 is arranged. in the passage 19. This permits the air to escape from the passage 19 and thus in connection with the needle valve varies the pressure in the passage 19 and cylinder 17- as the receiver pressure varies,

the leak of minute opening intensifying this This relief device or unloader is fully described in my Patent #962,551

dated June 28th, 1910. Briefly, its operation is as follows :The compressor starting with no receiver pressure, the valve 14; is wide open. When the receiver pressure passes the predetermined minimum this pressure operating on the piston 22 opens the needle valve 21. The air passin'g'to the cylinder 17 exerts pressure on the piston 16. As this pressure increases the piston is moved downwardly gradually. closing the valve 14 and thus varying the amount of air taken into the compressor-at each stroke. When the receiver pressure reaches the desired maximum the valve is entirely closed, thus cutting off the intake. As the receiver pressure decreases the reverse ofthis operation takes place.

The motor valve 9 has the stem 28. This stem passes through a gland or stufiing box 29 in the body 6 and'is connected with the piston 30. The piston 30 is arranged in the cylinder 31 secured to the frame 32 extending from the body 6, the frame 32 being open at the sides permitting access to the stuffing box 29 and also sub ecting the outer .end of the piston 30 to atmospheric pressure The cylinder 31 is connected to the intake 4 by a pipe 4. The spring 33 opposes the initial movement of the piston, that is, the movement closing the valve 9. A screw 34 extends through the rear end of the cylinder 31 and limits the extreme movement of the piston 30 and consequently limits the closing movement of the valve 9 so that under all conditions there is a slight opening of the valve to insure the continued running of the motor.

So .far as described this device is not broadly new. Its operation is as follows As heretofore made the valve 9 in its initial position and before pressure is developed in the receiver is m'aintained in an open position by means of the spring 33. Inasmuch as the valve 14 under these conditions is practically wide open there is very little or no reduction in pressure inthe intake 4.

' Consequently under these conditions, the

valve 9 remains wide open until the receiver pressure reaches a pressure which will operate the relief device so as to reduce the pressure in the intake 4. When this occurs this reduced pressure in the intake 4 is accompanied by a reduced pressure'in the cylinder 31, the piston being subjected to atoperator through some other means of control, ordinarily a throttle valve. I obviate this difliculty by the following means: A stem 35 extends through the gland 36 in the wallof the body 6 into the path of the valve 9. The rear end of the stem is secured to a piston 37. The piston 37 operates in a cylmospheric pressure on its outer face movesv in opposition to the spring 33 to close the valve 9. In a relief device that operates as a regulator as well as a relief device as shown in the drawings herewith, this closing of the valve 9 will be gradual, cutting ofl the motor valve or steam gradually as the load on the compressor is reduced.

Ase before stated, the difliculty with this structure is that up to the time there is developed in the receiver a normal pressure, the relief device is Wide open. Consequently in starting or where there is a sudden drop in pressure there is no reduction of pressure in the cylinder 31 and the valve 9 remains wide open. Inasmuch as there is no receiver pressure to oppose the motor and the motor is supplied with a full complement of steamthe compressor will run away unless it is checked or retarded by the action of the inder 38. The stem passes through a stuffmg box 39 at the front end of the cylinder. A pipe 40 connects thecylin'der with the receiver by way of the discharge pipe 5. A- screw 41 is arranged against the piston 37.- It extends through ayoke 42. Springs 43' are tensioned between the yoke 42 and lugs 44 extending from the frame 45,- the frame 45 being secured to the valve body 6 and supportin the cylinder 38. The springs are adjusted fiy means ofthe screws 46, the screws being locked in adjustment by nuts 47. In the position of the parts shown in the drawings, the receiver is at maximum pressure. With no pressure in the receiver, the piston 37 is forced forward under the influence of the springs 43 carrying with it the stem 35. The stem 35 contacts the valve 9 and the springs 43 being stronger than the spring 33, the valve 9 assumes a closed initial osition, or in other words, apotion substantially such as is shown in the drawings. As the receiver pressure increases, this pressure is communicated to the cylinder 38 and operating on the piston 37 forces the piston outwardly against the excess pressure of the springs 43 thus withdrawing the stem 35 and permitting the opening of the valve 9 under the influence of the spring 33. This outward movement of the piston 37 and with it the stem 35 is gradual, following the pressure as it increases in the receiver. In this wa the valve 9 is automatically retarded 1n the initial starting of the compressor or when there is a drop in pressure so as to prevent its running away. After normal pressure has been developed in the receiver, the piston 37 is forced outward so as to carry the stem out of the range of the normal movement of the valve 9 and this mechanism during the normal operation of the compressor is out of action.

What I claim as new is 1. In a pump regulating mechanism, the combination of a relief device; a controlling valve for the pump motor; and controlling means for said-valve opening and closing said valve as the relief device operates, said means being subjected to pressures varying sures varying as the discharge pressure varies to vary the opening of the valve as the discharge pressure varies.

3. In a pump regulating mechanism, the combination of an intake relief device; means controlled by discharge pressure for actuating said reliefdevice; a controlling valve for the pump motor; a valve motor subjected to intake pressure actuating the valve as the relief device is actuated; and a retarding motor subjected to pressures varying as the discharge pressure varies for retarding the opening of the valve With low discharge pressures.

4. In a pump regulating mechanism; the combination of an intake relief device; means controlled by discharge pressure for actuating said relief device; a controlling valve vfor the pump motor; a valve mot-or subjected to intake pressure actuating the valve as the relief device is actuated; and a retarding motor subjected to pressures varying as the discharge pressure varies for retarding the valve to open the valve gradually as the discharge pressure rises from low pressures to normal pressures.

5. In a pump regulating mechanism, the combination of an intake relief device; a motor controlling valve; a motor actuating the valve, said motor beingconnected to the intake side of the device and operating to close the valve as the intake pressure decreases; a retarding mechanism comprising a cylinder; a stem extending from said cylinder into the path of said valve; a piston operating on the stem; a pump discharge connection for said cylinder, said connection delivering fluid under pressureto actu ate the piston to carry the stem out of the path of the valve; and springs opposing the action of the piston.

(3. In a pump regulating mechanism, the combination of an intake relief device; a motor controlling valve; a motor actuating the valve, said motor being connected to the intake side of the device and operating to close the valve as the intake pressure decreases; a retarding mechanism comprising a cylinder; a stem extending from said cylindcr into the path of said valve; a piston operating on the stem; a pump discharge connection for said cylinder, said connection delivering fluid under pressure to actuate the, piston to carry the stem out of the path of the valve; springs opposing the action of the piston; and means for adjusting the spring pressure.

7. In a'pump regulating mechanism, the combination of an intake relief device; means controlled by discharge pressure for actuating said relief device; a controlling valve for the pump motor; a valve motor subjected to intake pressure actuating the valve as the relief device is actuated; a retarding motor subjected to pressures varying as the discharge pressure varies for retarding the opening of the valve with low discharge pressures; and means for adjusting the retarding motor to adjust it to varying pressures.

8. In a pump regulating mechanism, the combination of an intake relief device adapted to vary an intake opening to regulate the intake; means controlled by discharge pres sure for actuating said relief device; a controlling valve for the pump motor; a valve motor subjected to intake pressure actuating the valve as the relief device is actuated; and a retarding motor subjected to pressures varying as the discharge pressure varies for retarding the opening of the valve with low discharge pressures.

9. In a pump regulating mechanism, the combination of an intake relief device; a motor controlling valve; a stem on said valve; a piston connected to said stem; a cylinder in which said piston operates; a connection leading from the intake side of the relief device to said cylinder; a retard ing device comprising a stem adapted to be,

springs to vary the length and strength of the springs.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

RUDOLPH CONRADER. Witnesses:

B. M. I-TARTMAN, V. C. Hess. 

